ISO C++
ISO C++
backwards
backwards
Backwards Compatibility
Backwards Compatibility
First
First
The first generation GNU C++ library was called libg++. It was a
The first generation GNU C++ library was called libg++. It was a
separate GNU project, although reliably paired with GCC. Rumors imply
separate GNU project, although reliably paired with GCC. Rumors imply
that it had a working relationship with at least two kinds of
that it had a working relationship with at least two kinds of
dinosaur.
dinosaur.
Some background: libg++ was designed and created when there was no
Some background: libg++ was designed and created when there was no
ISO standard to provide guidance. Classes like linked lists are now
ISO standard to provide guidance. Classes like linked lists are now
provided for by list<T> and do not need to be
provided for by list<T> and do not need to be
created by genclass . (For that matter, templates exist
created by genclass . (For that matter, templates exist
now and are well-supported, whereas genclass (mostly) predates them.)
now and are well-supported, whereas genclass (mostly) predates them.)
There are other classes in libg++ that are not specified in the
There are other classes in libg++ that are not specified in the
ISO Standard (e.g., statistical analysis). While there are a lot of
ISO Standard (e.g., statistical analysis). While there are a lot of
really useful things that are used by a lot of people, the Standards
really useful things that are used by a lot of people, the Standards
Committee couldn't include everything, and so a lot of those
Committee couldn't include everything, and so a lot of those
obvious
classes didn't get included.
obvious
classes didn't get included.
Known Issues include many of the limitations of its immediate ancestor.
Known Issues include many of the limitations of its immediate ancestor.
Portability notes and known implementation limitations are as follows.
Portability notes and known implementation limitations are as follows.
No ios_base
No ios_base
At least some older implementations don't have std::ios_base
, so you should use std::ios::badbit
, std::ios::failbit
and std::ios::eofbit
and std::ios::goodbit
.
At least some older implementations don't have std::ios_base
, so you should use std::ios::badbit
, std::ios::failbit
and std::ios::eofbit
and std::ios::goodbit
.
No cout
in ostream.h
, no cin
in istream.h
No cout
in ostream.h
, no cin
in istream.h
In earlier versions of the standard,
In earlier versions of the standard,
,
,
and
and
used to define
used to define
cout
, cin
and so on. ISO C++ specifies that one needs to include
cout
, cin
and so on. ISO C++ specifies that one needs to include
explicitly to get the required definitions.
explicitly to get the required definitions.
Some include adjustment may be required.
Some include adjustment may be required.
This project is no longer maintained or supported, and the sources
This project is no longer maintained or supported, and the sources
archived. For the desperate,
archived. For the desperate,
the GCC extensions
the GCC extensions
page describes where to find the last libg++ source. The code is
page describes where to find the last libg++ source. The code is
considered replaced and rewritten.
considered replaced and rewritten.
Second
Second
The second generation GNU C++ library was called libstdc++, or
The second generation GNU C++ library was called libstdc++, or
libstdc++-v2. It spans the time between libg++ and pre-ISO C++
libstdc++-v2. It spans the time between libg++ and pre-ISO C++
standardization and is usually associated with the following GCC
standardization and is usually associated with the following GCC
releases: egcs 1.x, gcc 2.95, and gcc 2.96.
releases: egcs 1.x, gcc 2.95, and gcc 2.96.
The STL portions of this library are based on SGI/HP STL release 3.11.
The STL portions of this library are based on SGI/HP STL release 3.11.
This project is no longer maintained or supported, and the sources
This project is no longer maintained or supported, and the sources
archived. The code is considered replaced and rewritten.
archived. The code is considered replaced and rewritten.
Portability notes and known implementation limitations are as follows.
Portability notes and known implementation limitations are as follows.
Namespace std::
not supported
Namespace std::
not supported
Some care is required to support C++ compiler and or library
Some care is required to support C++ compiler and or library
implementation that do not have the standard library in
implementation that do not have the standard library in
namespace std
.
namespace std
.
The following sections list some possible solutions to support compilers
The following sections list some possible solutions to support compilers
that cannot ignore std::
-qualified names.
that cannot ignore std::
-qualified names.
First, see if the compiler has a flag for this. Namespace
First, see if the compiler has a flag for this. Namespace
back-portability-issues are generally not a problem for g++
back-portability-issues are generally not a problem for g++
compilers that do not have libstdc++ in std::
, as the
compilers that do not have libstdc++ in std::
, as the
compilers use -fno-honor-std
(ignore
compilers use -fno-honor-std
(ignore
std::
, :: = std::
) by default. That is,
std::
, :: = std::
) by default. That is,
the responsibility for enabling or disabling std::
is
the responsibility for enabling or disabling std::
is
on the user; the maintainer does not have to care about it. This
on the user; the maintainer does not have to care about it. This
probably applies to some other compilers as well.
probably applies to some other compilers as well.
Second, experiment with a variety of pre-processor tricks.
Second, experiment with a variety of pre-processor tricks.
By defining std
as a macro, fully-qualified namespace
By defining std
as a macro, fully-qualified namespace
calls become global. Volia.
calls become global. Volia.
#ifdef WICKEDLY_OLD_COMPILER
#ifdef WICKEDLY_OLD_COMPILER
# define std
# define std
#endif
#endif
Thanks to Juergen Heinzl who posted this solution on gnu.gcc.help.
Thanks to Juergen Heinzl who posted this solution on gnu.gcc.help.
Another pre-processor based approach is to define a macro
Another pre-processor based approach is to define a macro
NAMESPACE_STD
, which is defined to either
NAMESPACE_STD
, which is defined to either
or std
based on a compile-type
or std
based on a compile-type
test. On GNU systems, this can be done with autotools by means of
test. On GNU systems, this can be done with autotools by means of
an autoconf test (see below) for HAVE_NAMESPACE_STD
,
an autoconf test (see below) for HAVE_NAMESPACE_STD
,
then using that to set a value for the NAMESPACE_STD
then using that to set a value for the NAMESPACE_STD
macro. At that point, one is able to use
macro. At that point, one is able to use
NAMESPACE_STD::string
, which will evaluate to
NAMESPACE_STD::string
, which will evaluate to
std::string
or ::string
(i.e., in the
std::string
or ::string
(i.e., in the
global namespace on systems that do not put string
in
global namespace on systems that do not put string
in
std::
).
std::
).
dnl @synopsis AC_CXX_NAMESPACE_STD
dnl @synopsis AC_CXX_NAMESPACE_STD
dnl
dnl
dnl If the compiler supports namespace std, define
dnl If the compiler supports namespace std, define
dnl HAVE_NAMESPACE_STD.
dnl HAVE_NAMESPACE_STD.
dnl
dnl
dnl @category Cxx
dnl @category Cxx
dnl @author Todd Veldhuizen
dnl @author Todd Veldhuizen
dnl @author Luc Maisonobe <luc@spaceroots.org>
dnl @author Luc Maisonobe <luc@spaceroots.org>
dnl @version 2004-02-04
dnl @version 2004-02-04
dnl @license AllPermissive
dnl @license AllPermissive
AC_DEFUN([AC_CXX_NAMESPACE_STD], [
AC_DEFUN([AC_CXX_NAMESPACE_STD], [
AC_CACHE_CHECK(if g++ supports namespace std,
AC_CACHE_CHECK(if g++ supports namespace std,
ac_cv_cxx_have_std_namespace,
ac_cv_cxx_have_std_namespace,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([#include <iostream>
AC_TRY_COMPILE([#include <iostream>
std::istream& is = std::cin;],,
std::istream& is = std::cin;],,
ac_cv_cxx_have_std_namespace=yes, ac_cv_cxx_have_std_namespace=no)
ac_cv_cxx_have_std_namespace=yes, ac_cv_cxx_have_std_namespace=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_have_std_namespace" = yes; then
if test "$ac_cv_cxx_have_std_namespace" = yes; then
AC_DEFINE(HAVE_NAMESPACE_STD,,[Define if g++ supports namespace std. ])
AC_DEFINE(HAVE_NAMESPACE_STD,,[Define if g++ supports namespace std. ])
fi
fi
])
])
Illegal iterator usage
Illegal iterator usage
The following illustrate implementation-allowed illegal iterator
The following illustrate implementation-allowed illegal iterator
use, and then correct use.
use, and then correct use.
you cannot do ostream::operator<<(iterator)
you cannot do ostream::operator<<(iterator)
to print the address of the iterator => use
to print the address of the iterator => use
operator<< &*iterator
instead
operator<< &*iterator
instead
you cannot clear an iterator's reference (iterator =
you cannot clear an iterator's reference (iterator =
0
) => use iterator = iterator_type();
0
) => use iterator = iterator_type();
if (iterator)
won't work any more => use
if (iterator)
won't work any more => use
if (iterator != iterator_type())
if (iterator != iterator_type())
isspace
from is a macro
isspace
from is a macro
Glibc 2.0.x and 2.1.x define
Glibc 2.0.x and 2.1.x define
class="headerfile">ctype.h functionality as macros
class="headerfile">ctype.h functionality as macros
(isspace, isalpha etc.).
(isspace, isalpha etc.).
This implementations of libstdc++, however, keep these functions
This implementations of libstdc++, however, keep these functions
as macros, and so it is not back-portable to use fully qualified
as macros, and so it is not back-portable to use fully qualified
names. For example:
names. For example:
#include <cctype>
#include <cctype>
int main() { std::isspace('X'); }
int main() { std::isspace('X'); }
Results in something like this:
Results in something like this:
std:: (__ctype_b[(int) ( ( 'X' ) )] & (unsigned short int) _ISspace ) ;
std:: (__ctype_b[(int) ( ( 'X' ) )] & (unsigned short int) _ISspace ) ;
A solution is to modify a header-file so that the compiler tells
A solution is to modify a header-file so that the compiler tells
to define functions
to define functions
instead of macros:
instead of macros:
// This keeps isalnum, et al from being propagated as macros.
// This keeps isalnum, et al from being propagated as macros.
#if __linux__
#if __linux__
# define __NO_CTYPE 1
# define __NO_CTYPE 1
#endif
#endif
Then, include
Then, include
Another problem arises if you put a using namespace
Another problem arises if you put a using namespace
std;
declaration at the top, and include
std;
declaration at the top, and include
class="headerfile">ctype.h. This will result in
class="headerfile">ctype.h. This will result in
ambiguities between the definitions in the global namespace
ambiguities between the definitions in the global namespace
() and the
() and the
definitions in namespace std::
definitions in namespace std::
(<cctype>
).
(<cctype>
).
No vector::at
, deque::at
, string::at
No vector::at
, deque::at
, string::at
One solution is to add an autoconf-test for this:
One solution is to add an autoconf-test for this:
AC_MSG_CHECKING(for container::at)
AC_MSG_CHECKING(for container::at)
AC_TRY_COMPILE(
AC_TRY_COMPILE(
[
[
#include <vector>
#include <vector>
#include <deque>
#include <deque>
#include <string>
#include <string>
using namespace std;
using namespace std;
],
],
[
[
deque<int> test_deque(3);
deque<int> test_deque(3);
test_deque.at(2);
test_deque.at(2);
vector<int> test_vector(2);
vector<int> test_vector(2);
test_vector.at(1);
test_vector.at(1);
string test_string(test_string
);
string test_string(test_string
);
test_string.at(3);
test_string.at(3);
],
],
[AC_MSG_RESULT(yes)
[AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_CONTAINER_AT)],
AC_DEFINE(HAVE_CONTAINER_AT)],
[AC_MSG_RESULT(no)])
[AC_MSG_RESULT(no)])
If you are using other (non-GNU) compilers it might be a good idea
If you are using other (non-GNU) compilers it might be a good idea
to check for string::at
separately.
to check for string::at
separately.
No std::char_traits<char>::eof
No std::char_traits<char>::eof
Use some kind of autoconf test, plus this:
Use some kind of autoconf test, plus this:
#ifdef HAVE_CHAR_TRAITS
#ifdef HAVE_CHAR_TRAITS
#define CPP_EOF std::char_traits<char>::eof()
#define CPP_EOF std::char_traits<char>::eof()
#else
#else
#define CPP_EOF EOF
#define CPP_EOF EOF
#endif
#endif
No string::clear
No string::clear
There are two functions for deleting the contents of a string:
There are two functions for deleting the contents of a string:
clear
and erase
(the latter returns the
clear
and erase
(the latter returns the
string).
string).
void
void
clear() { _M_mutate(0, this->size(), 0); }
clear() { _M_mutate(0, this->size(), 0); }
basic_string&
basic_string&
erase(size_type __pos = 0, size_type __n = npos)
erase(size_type __pos = 0, size_type __n = npos)
{
{
return this->replace(_M_check(__pos), _M_fold(__pos, __n),
return this->replace(_M_check(__pos), _M_fold(__pos, __n),
_M_data(), _M_data());
_M_data(), _M_data());
}
}
Unfortunately, clear
is not implemented in this
Unfortunately, clear
is not implemented in this
version, so you should use erase
(which is probably
version, so you should use erase
(which is probably
faster than operator=(charT*)
).
faster than operator=(charT*)
).
Removal of ostream::form
and istream::scan
Removal of ostream::form
and istream::scan
extensions
extensions
These are no longer supported. Please use stringstreams instead.
These are no longer supported. Please use stringstreams instead.
No basic_stringbuf
, basic_stringstream
No basic_stringbuf
, basic_stringstream
Although the ISO standard i/ostringstream
-classes are
Although the ISO standard i/ostringstream
-classes are
provided, (), for
provided, (), for
compatibility with older implementations the pre-ISO
compatibility with older implementations the pre-ISO
i/ostrstream
(
i/ostrstream
(
class="headerfile">strstream) interface is also provided,
class="headerfile">strstream) interface is also provided,
with these caveats:
with these caveats:
strstream
is considered to be deprecated
strstream
is considered to be deprecated
strstream
is limited to char
strstream
is limited to char
with ostringstream
you don't have to take care of
with ostringstream
you don't have to take care of
terminating the string or freeing its memory
terminating the string or freeing its memory
istringstream
can be re-filled (clear();
istringstream
can be re-filled (clear();
str(input);)
str(input);)
You can then use output-stringstreams like this:
You can then use output-stringstreams like this:
#ifdef HAVE_SSTREAM
#ifdef HAVE_SSTREAM
# include <sstream>
# include <sstream>
#else
#else
# include <strstream>
# include <strstream>
#endif
#endif
#ifdef HAVE_SSTREAM
#ifdef HAVE_SSTREAM
std::ostringstream oss;
std::ostringstream oss;
#else
#else
std::ostrstream oss;
std::ostrstream oss;
#endif
#endif
oss << Name=
<< m_name << , number=
<< m_number << std::endl;
oss << Name=
<< m_name << , number=
<< m_number << std::endl;
...
...
#ifndef HAVE_SSTREAM
#ifndef HAVE_SSTREAM
oss << std::ends; // terminate the char*-string
oss << std::ends; // terminate the char*-string
#endif
#endif
// str() returns char* for ostrstream and a string for ostringstream
// str() returns char* for ostrstream and a string for ostringstream
// this also causes ostrstream to think that the buffer's memory
// this also causes ostrstream to think that the buffer's memory
// is yours
// is yours
m_label.set_text(oss.str());
m_label.set_text(oss.str());
#ifndef HAVE_SSTREAM
#ifndef HAVE_SSTREAM
// let the ostrstream take care of freeing the memory
// let the ostrstream take care of freeing the memory
oss.freeze(false);
oss.freeze(false);
#endif
#endif
Input-stringstreams can be used similarly:
Input-stringstreams can be used similarly:
std::string input;
std::string input;
...
...
#ifdef HAVE_SSTREAM
#ifdef HAVE_SSTREAM
std::istringstream iss(input);
std::istringstream iss(input);
#else
#else
std::istrstream iss(input.c_str());
std::istrstream iss(input.c_str());
#endif
#endif
int i;
int i;
iss >> i;
iss >> i;
One (the only?) restriction is that an istrstream cannot be re-filled:
One (the only?) restriction is that an istrstream cannot be re-filled:
std::istringstream iss(numerator);
std::istringstream iss(numerator);
iss >> m_num;
iss >> m_num;
// this is not possible with istrstream
// this is not possible with istrstream
iss.clear();
iss.clear();
iss.str(denominator);
iss.str(denominator);
iss >> m_den;
iss >> m_den;
If you don't care about speed, you can put these conversions in
If you don't care about speed, you can put these conversions in
a template-function:
a template-function:
template <class X>
template <class X>
void fromString(const string& input, X& any)
void fromString(const string& input, X& any)
{
{
#ifdef HAVE_SSTREAM
#ifdef HAVE_SSTREAM
std::istringstream iss(input);
std::istringstream iss(input);
#else
#else
std::istrstream iss(input.c_str());
std::istrstream iss(input.c_str());
#endif
#endif
X temp;
X temp;
iss >> temp;
iss >> temp;
if (iss.fail())
if (iss.fail())
throw runtime_error(..)
throw runtime_error(..)
any = temp;
any = temp;
}
}
Another example of using stringstreams is in
Another example of using stringstreams is in
linkend="strings.string.shrink">this howto.
linkend="strings.string.shrink">this howto.
There is additional information in the libstdc++-v2 info files, in
There is additional information in the libstdc++-v2 info files, in
particular info iostream
.
particular info iostream
.
Little or no wide character support
Little or no wide character support
Classes wstring and
Classes wstring and
char_traits<wchar_t> are
char_traits<wchar_t> are
not supported.
not supported.
No templatized iostreams
No templatized iostreams
Classes wfilebuf and
Classes wfilebuf and
wstringstream are not supported.
wstringstream are not supported.
Thread safety issues
Thread safety issues
Earlier GCC releases had a somewhat different approach to
Earlier GCC releases had a somewhat different approach to
threading configuration and proper compilation. Before GCC 3.0,
threading configuration and proper compilation. Before GCC 3.0,
configuration of the threading model was dictated by compiler
configuration of the threading model was dictated by compiler
command-line options and macros (both of which were somewhat
command-line options and macros (both of which were somewhat
thread-implementation and port-specific). There were no
thread-implementation and port-specific). There were no
guarantees related to being able to link code compiled with one
guarantees related to being able to link code compiled with one
set of options and macro setting with another set.
set of options and macro setting with another set.
For GCC 3.0, configuration of the threading model used with
For GCC 3.0, configuration of the threading model used with
libraries and user-code is performed when GCC is configured and
libraries and user-code is performed when GCC is configured and
built using the --enable-threads and --disable-threads options.
built using the --enable-threads and --disable-threads options.
The ABI is stable for symbol name-mangling and limited functional
The ABI is stable for symbol name-mangling and limited functional
compatibility exists between code compiled under different
compatibility exists between code compiled under different
threading models.
threading models.
The libstdc++ library has been designed so that it can be used in
The libstdc++ library has been designed so that it can be used in
multithreaded applications (with libstdc++-v2 this was only true
multithreaded applications (with libstdc++-v2 this was only true
of the STL parts.) The first problem is finding a
of the STL parts.) The first problem is finding a
fast method of implementation portable to
fast method of implementation portable to
all platforms. Due to historical reasons, some of the library is
all platforms. Due to historical reasons, some of the library is
written against per-CPU-architecture spinlocks and other parts
written against per-CPU-architecture spinlocks and other parts
against the gthr.h abstraction layer which is provided by gcc. A
against the gthr.h abstraction layer which is provided by gcc. A
minor problem that pops up every so often is different
minor problem that pops up every so often is different
interpretations of what "thread-safe" means for a
interpretations of what "thread-safe" means for a
library (not a general program). We currently use the
library (not a general program). We currently use the
url="http://www.sgi.com/tech/stl/thread_safety.html">same
url="http://www.sgi.com/tech/stl/thread_safety.html">same
definition that SGI uses for their STL subset. However,
definition that SGI uses for their STL subset. However,
the exception for read-only containers only applies to the STL
the exception for read-only containers only applies to the STL
components. This definition is widely-used and something similar
components. This definition is widely-used and something similar
will be used in the next version of the C++ standard library.
will be used in the next version of the C++ standard library.
Here is a small link farm to threads (no pun) in the mail
Here is a small link farm to threads (no pun) in the mail
archives that discuss the threading problem. Each link is to the
archives that discuss the threading problem. Each link is to the
first relevant message in the thread; from there you can use
first relevant message in the thread; from there you can use
"Thread Next" to move down the thread. This farm is in
"Thread Next" to move down the thread. This farm is in
latest-to-oldest order.
latest-to-oldest order.
Our threading expert Loren gives a breakdown of
Our threading expert Loren gives a breakdown of
url="http://gcc.gnu.org/ml/libstdc++/2001-10/msg00024.html">the
url="http://gcc.gnu.org/ml/libstdc++/2001-10/msg00024.html">the
six situations involving threads for the 3.0
six situations involving threads for the 3.0
release series.
release series.
This message inspired a recent updating of issues with
This message inspired a recent updating of issues with
threading and the SGI STL library. It also contains some
threading and the SGI STL library. It also contains some
example POSIX-multithreaded STL code.
example POSIX-multithreaded STL code.
(A large selection of links to older messages has been removed;
(A large selection of links to older messages has been removed;
many of the messages from 1999 were lost in a disk crash, and the
many of the messages from 1999 were lost in a disk crash, and the
few people with access to the backup tapes have been too swamped
few people with access to the backup tapes have been too swamped
with work to restore them. Many of the points have been
with work to restore them. Many of the points have been
superseded anyhow.)
superseded anyhow.)
Third
Third
The third generation GNU C++ library is called libstdc++, or
The third generation GNU C++ library is called libstdc++, or
libstdc++-v3.
libstdc++-v3.
The subset commonly known as the Standard Template Library
The subset commonly known as the Standard Template Library
(chapters 23 through 25, mostly) is adapted from the final release
(chapters 23 through 25, mostly) is adapted from the final release
of the SGI STL (version 3.3), with extensive changes.
of the SGI STL (version 3.3), with extensive changes.
A more formal description of the V3 goals can be found in the
A more formal description of the V3 goals can be found in the
official design document.
official design document.
Portability notes and known implementation limitations are as follows.
Portability notes and known implementation limitations are as follows.
Pre-ISO headers moved to backwards or removed
Pre-ISO headers moved to backwards or removed
The pre-ISO C++ headers
The pre-ISO C++ headers
(iostream.h
, defalloc.h
etc.) are
(iostream.h
, defalloc.h
etc.) are
available, unlike previous libstdc++ versions, but inclusion
available, unlike previous libstdc++ versions, but inclusion
generates a warning that you are using deprecated headers.
generates a warning that you are using deprecated headers.
This compatibility layer is constructed by including the
This compatibility layer is constructed by including the
standard C++ headers, and injecting any items in
standard C++ headers, and injecting any items in
std::
into the global namespace.
std::
into the global namespace.
For those of you new to ISO C++ (welcome, time travelers!), no,
For those of you new to ISO C++ (welcome, time travelers!), no,
that isn't a typo. Yes, the headers really have new names.
that isn't a typo. Yes, the headers really have new names.
Marshall Cline's C++ FAQ Lite has a good explanation in item
Marshall Cline's C++ FAQ Lite has a good explanation in item
[27.4].
[27.4].
Some include adjustment may be required. What follows is an
Some include adjustment may be required. What follows is an
autoconf test that defines PRE_STDCXX_HEADERS
when they
autoconf test that defines PRE_STDCXX_HEADERS
when they
exist.
exist.
# AC_HEADER_PRE_STDCXX
# AC_HEADER_PRE_STDCXX
AC_DEFUN([AC_HEADER_PRE_STDCXX], [
AC_DEFUN([AC_HEADER_PRE_STDCXX], [
AC_CACHE_CHECK(for pre-ISO C++ include files,
AC_CACHE_CHECK(for pre-ISO C++ include files,
ac_cv_cxx_pre_stdcxx,
ac_cv_cxx_pre_stdcxx,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -Wno-deprecated"
CXXFLAGS="$CXXFLAGS -Wno-deprecated"
# Omit defalloc.h, as compilation with newer compilers is problematic.
# Omit defalloc.h, as compilation with newer compilers is problematic.
AC_TRY_COMPILE([
AC_TRY_COMPILE([
#include <new.h>
#include <new.h>
#include <iterator.h>
#include <iterator.h>
#include <alloc.h>
#include <alloc.h>
#include <set.h>
#include <set.h>
#include <hashtable.h>
#include <hashtable.h>
#include <hash_set.h>
#include <hash_set.h>
#include <fstream.h>
#include <fstream.h>
#include <tempbuf.h>
#include <tempbuf.h>
#include <istream.h>
#include <istream.h>
#include <bvector.h>
#include <bvector.h>
#include <stack.h>
#include <stack.h>
#include <rope.h>
#include <rope.h>
#include <complex.h>
#include <complex.h>
#include <ostream.h>
#include <ostream.h>
#include <heap.h>
#include <heap.h>
#include <iostream.h>
#include <iostream.h>
#include <function.h>
#include <function.h>
#include <multimap.h>
#include <multimap.h>
#include <pair.h>
#include <pair.h>
#include <stream.h>
#include <stream.h>
#include <iomanip.h>
#include <iomanip.h>
#include <slist.h>
#include <slist.h>
#include <tree.h>
#include <tree.h>
#include <vector.h>
#include <vector.h>
#include <deque.h>
#include <deque.h>
#include <multiset.h>
#include <multiset.h>
#include <list.h>
#include <list.h>
#include <map.h>
#include <map.h>
#include <algobase.h>
#include <algobase.h>
#include <hash_map.h>
#include <hash_map.h>
#include <algo.h>
#include <algo.h>
#include <queue.h>
#include <queue.h>
#include <streambuf.h>
#include <streambuf.h>
],,
],,
ac_cv_cxx_pre_stdcxx=yes, ac_cv_cxx_pre_stdcxx=no)
ac_cv_cxx_pre_stdcxx=yes, ac_cv_cxx_pre_stdcxx=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_pre_stdcxx" = yes; then
if test "$ac_cv_cxx_pre_stdcxx" = yes; then
AC_DEFINE(PRE_STDCXX_HEADERS,,[Define if pre-ISO C++ header files are present. ])
AC_DEFINE(PRE_STDCXX_HEADERS,,[Define if pre-ISO C++ header files are present. ])
fi
fi
])
])
Porting between pre-ISO headers and ISO headers is simple: headers
Porting between pre-ISO headers and ISO headers is simple: headers
like can be replaced with and a using
like can be replaced with and a using
directive using namespace std;
can be put at the global
directive using namespace std;
can be put at the global
scope. This should be enough to get this code compiling, assuming the
scope. This should be enough to get this code compiling, assuming the
other usage is correct.
other usage is correct.
Extension headers hash_map, hash_set moved to ext or backwards
Extension headers hash_map, hash_set moved to ext or backwards
At this time most of the features of the SGI STL extension have been
At this time most of the features of the SGI STL extension have been
replaced by standardized libraries.
replaced by standardized libraries.
In particular, the unordered_map and unordered_set containers of TR1
In particular, the unordered_map and unordered_set containers of TR1
are suitable replacement for the non-standard hash_map and hash_set
are suitable replacement for the non-standard hash_map and hash_set
containers in the SGI STL.
containers in the SGI STL.
Header files and moved
Header files and moved
to and ,
to and ,
respectively. At the same time, all types in these files are enclosed
respectively. At the same time, all types in these files are enclosed
in namespace __gnu_cxx
. Later versions move deprecate
in namespace __gnu_cxx
. Later versions move deprecate
these files, and suggest using TR1's
these files, and suggest using TR1's
and instead.
and instead.
The extensions are no longer in the global or std
The extensions are no longer in the global or std
namespaces, instead they are declared in the __gnu_cxx
namespaces, instead they are declared in the __gnu_cxx
namespace. For maximum portability, consider defining a namespace
namespace. For maximum portability, consider defining a namespace
alias to use to talk about extensions, e.g.:
alias to use to talk about extensions, e.g.:
#ifdef __GNUC__
#ifdef __GNUC__
#if __GNUC__ < 3
#if __GNUC__ < 3
#include <hash_map.h>
#include <hash_map.h>
namespace extension { using ::hash_map; }; // inherit globals
namespace extension { using ::hash_map; }; // inherit globals
#else
#else
#include <backward/hash_map>
#include <backward/hash_map>
#if __GNUC__ == 3 && __GNUC_MINOR__ == 0
#if __GNUC__ == 3 && __GNUC_MINOR__ == 0
namespace extension = std; // GCC 3.0
namespace extension = std; // GCC 3.0
#else
#else
namespace extension = ::__gnu_cxx; // GCC 3.1 and later
namespace extension = ::__gnu_cxx; // GCC 3.1 and later
#endif
#endif
#endif
#endif
#else // ... there are other compilers, right?
#else // ... there are other compilers, right?
namespace extension = std;
namespace extension = std;
#endif
#endif
extension::hash_map<int,int> my_map;
extension::hash_map<int,int> my_map;
This is a bit cleaner than defining typedefs for all the
This is a bit cleaner than defining typedefs for all the
instantiations you might need.
instantiations you might need.
The following autoconf tests check for working HP/SGI hash containers.
The following autoconf tests check for working HP/SGI hash containers.
# AC_HEADER_EXT_HASH_MAP
# AC_HEADER_EXT_HASH_MAP
AC_DEFUN([AC_HEADER_EXT_HASH_MAP], [
AC_DEFUN([AC_HEADER_EXT_HASH_MAP], [
AC_CACHE_CHECK(for ext/hash_map,
AC_CACHE_CHECK(for ext/hash_map,
ac_cv_cxx_ext_hash_map,
ac_cv_cxx_ext_hash_map,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -Werror"
CXXFLAGS="$CXXFLAGS -Werror"
AC_TRY_COMPILE([#include <ext/hash_map>], [using __gnu_cxx::hash_map;],
AC_TRY_COMPILE([#include <ext/hash_map>], [using __gnu_cxx::hash_map;],
ac_cv_cxx_ext_hash_map=yes, ac_cv_cxx_ext_hash_map=no)
ac_cv_cxx_ext_hash_map=yes, ac_cv_cxx_ext_hash_map=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_ext_hash_map" = yes; then
if test "$ac_cv_cxx_ext_hash_map" = yes; then
AC_DEFINE(HAVE_EXT_HASH_MAP,,[Define if ext/hash_map is present. ])
AC_DEFINE(HAVE_EXT_HASH_MAP,,[Define if ext/hash_map is present. ])
fi
fi
])
])
# AC_HEADER_EXT_HASH_SET
# AC_HEADER_EXT_HASH_SET
AC_DEFUN([AC_HEADER_EXT_HASH_SET], [
AC_DEFUN([AC_HEADER_EXT_HASH_SET], [
AC_CACHE_CHECK(for ext/hash_set,
AC_CACHE_CHECK(for ext/hash_set,
ac_cv_cxx_ext_hash_set,
ac_cv_cxx_ext_hash_set,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -Werror"
CXXFLAGS="$CXXFLAGS -Werror"
AC_TRY_COMPILE([#include <ext/hash_set>], [using __gnu_cxx::hash_set;],
AC_TRY_COMPILE([#include <ext/hash_set>], [using __gnu_cxx::hash_set;],
ac_cv_cxx_ext_hash_set=yes, ac_cv_cxx_ext_hash_set=no)
ac_cv_cxx_ext_hash_set=yes, ac_cv_cxx_ext_hash_set=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_ext_hash_set" = yes; then
if test "$ac_cv_cxx_ext_hash_set" = yes; then
AC_DEFINE(HAVE_EXT_HASH_SET,,[Define if ext/hash_set is present. ])
AC_DEFINE(HAVE_EXT_HASH_SET,,[Define if ext/hash_set is present. ])
fi
fi
])
])
No ios::nocreate/ios::noreplace
.
No ios::nocreate/ios::noreplace
.
The existence of ios::nocreate
being used for
The existence of ios::nocreate
being used for
input-streams has been confirmed, most probably because the author
input-streams has been confirmed, most probably because the author
thought it would be more correct to specify nocreate explicitly. So
thought it would be more correct to specify nocreate explicitly. So
it can be left out for input-streams.
it can be left out for input-streams.
For output streams, nocreate
is probably the default,
For output streams, nocreate
is probably the default,
unless you specify std::ios::trunc
? To be safe, you can
unless you specify std::ios::trunc
? To be safe, you can
open the file for reading, check if it has been opened, and then
open the file for reading, check if it has been opened, and then
decide whether you want to create/replace or not. To my knowledge,
decide whether you want to create/replace or not. To my knowledge,
even older implementations support app
, ate
even older implementations support app
, ate
and trunc
(except for app
?).
and trunc
(except for app
?).
No stream::attach(int fd)
No stream::attach(int fd)
Phil Edwards writes: It was considered and rejected for the ISO
Phil Edwards writes: It was considered and rejected for the ISO
standard. Not all environments use file descriptors. Of those
standard. Not all environments use file descriptors. Of those
that do, not all of them use integers to represent them.
that do, not all of them use integers to represent them.
For a portable solution (among systems which use
For a portable solution (among systems which use
file descriptors), you need to implement a subclass of
file descriptors), you need to implement a subclass of
std::streambuf
(or
std::streambuf
(or
std::basic_streambuf<..>
) which opens a file
std::basic_streambuf<..>
) which opens a file
given a descriptor, and then pass an instance of this to the
given a descriptor, and then pass an instance of this to the
stream-constructor.
stream-constructor.
An extension is available that implements this.
An extension is available that implements this.
contains a derived class called
contains a derived class called
__gnu_cxx::stdio_filebuf
.
__gnu_cxx::stdio_filebuf
.
This class can be constructed from a C FILE*
or a file
This class can be constructed from a C FILE*
or a file
descriptor, and provides the fd()
function.
descriptor, and provides the fd()
function.
For another example of this, refer to
For another example of this, refer to
fdstream example
fdstream example
by Nicolai Josuttis.
by Nicolai Josuttis.
Support for C++98 dialect.
Support for C++98 dialect.
Check for complete library coverage of the C++1998/2003 standard.
Check for complete library coverage of the C++1998/2003 standard.
# AC_HEADER_STDCXX_98
# AC_HEADER_STDCXX_98
AC_DEFUN([AC_HEADER_STDCXX_98], [
AC_DEFUN([AC_HEADER_STDCXX_98], [
AC_CACHE_CHECK(for ISO C++ 98 include files,
AC_CACHE_CHECK(for ISO C++ 98 include files,
ac_cv_cxx_stdcxx_98,
ac_cv_cxx_stdcxx_98,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([
AC_TRY_COMPILE([
#include <cassert>
#include <cassert>
#include <cctype>
#include <cctype>
#include <cerrno>
#include <cerrno>
#include <cfloat>
#include <cfloat>
#include <ciso646>
#include <ciso646>
#include <climits>
#include <climits>
#include <clocale>
#include <clocale>
#include <cmath>
#include <cmath>
#include <csetjmp>
#include <csetjmp>
#include <csignal>
#include <csignal>
#include <cstdarg>
#include <cstdarg>
#include <cstddef>
#include <cstddef>
#include <cstdio>
#include <cstdio>
#include <cstdlib>
#include <cstdlib>
#include <cstring>
#include <cstring>
#include <ctime>
#include <ctime>
#include <algorithm>
#include <algorithm>
#include <bitset>
#include <bitset>
#include <complex>
#include <complex>
#include <deque>
#include <deque>
#include <exception>
#include <exception>
#include <fstream>
#include <fstream>
#include <functional>
#include <functional>
#include <iomanip>
#include <iomanip>
#include <ios>
#include <ios>
#include <iosfwd>
#include <iosfwd>
#include <iostream>
#include <iostream>
#include <istream>
#include <istream>
#include <iterator>
#include <iterator>
#include <limits>
#include <limits>
#include <list>
#include <list>
#include <locale>
#include <locale>
#include <map>
#include <map>
#include <memory>
#include <memory>
#include <new>
#include <new>
#include <numeric>
#include <numeric>
#include <ostream>
#include <ostream>
#include <queue>
#include <queue>
#include <set>
#include <set>
#include <sstream>
#include <sstream>
#include <stack>
#include <stack>
#include <stdexcept>
#include <stdexcept>
#include <streambuf>
#include <streambuf>
#include <string>
#include <string>
#include <typeinfo>
#include <typeinfo>
#include <utility>
#include <utility>
#include <valarray>
#include <valarray>
#include <vector>
#include <vector>
],,
],,
ac_cv_cxx_stdcxx_98=yes, ac_cv_cxx_stdcxx_98=no)
ac_cv_cxx_stdcxx_98=yes, ac_cv_cxx_stdcxx_98=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_stdcxx_98" = yes; then
if test "$ac_cv_cxx_stdcxx_98" = yes; then
AC_DEFINE(STDCXX_98_HEADERS,,[Define if ISO C++ 1998 header files are present. ])
AC_DEFINE(STDCXX_98_HEADERS,,[Define if ISO C++ 1998 header files are present. ])
fi
fi
])
])
Support for C++TR1 dialect.
Support for C++TR1 dialect.
Check for library coverage of the TR1 standard.
Check for library coverage of the TR1 standard.
# AC_HEADER_STDCXX_TR1
# AC_HEADER_STDCXX_TR1
AC_DEFUN([AC_HEADER_STDCXX_TR1], [
AC_DEFUN([AC_HEADER_STDCXX_TR1], [
AC_CACHE_CHECK(for ISO C++ TR1 include files,
AC_CACHE_CHECK(for ISO C++ TR1 include files,
ac_cv_cxx_stdcxx_tr1,
ac_cv_cxx_stdcxx_tr1,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([
AC_TRY_COMPILE([
#include <tr1/array>
#include <tr1/array>
#include <tr1/ccomplex>
#include <tr1/ccomplex>
#include <tr1/cctype>
#include <tr1/cctype>
#include <tr1/cfenv>
#include <tr1/cfenv>
#include <tr1/cfloat>
#include <tr1/cfloat>
#include <tr1/cinttypes>
#include <tr1/cinttypes>
#include <tr1/climits>
#include <tr1/climits>
#include <tr1/cmath>
#include <tr1/cmath>
#include <tr1/complex>
#include <tr1/complex>
#include <tr1/cstdarg>
#include <tr1/cstdarg>
#include <tr1/cstdbool>
#include <tr1/cstdbool>
#include <tr1/cstdint>
#include <tr1/cstdint>
#include <tr1/cstdio>
#include <tr1/cstdio>
#include <tr1/cstdlib>
#include <tr1/cstdlib>
#include <tr1/ctgmath>
#include <tr1/ctgmath>
#include <tr1/ctime>
#include <tr1/ctime>
#include <tr1/cwchar>
#include <tr1/cwchar>
#include <tr1/cwctype>
#include <tr1/cwctype>
#include <tr1/functional>
#include <tr1/functional>
#include <tr1/memory>
#include <tr1/memory>
#include <tr1/random>
#include <tr1/random>
#include <tr1/regex>
#include <tr1/regex>
#include <tr1/tuple>
#include <tr1/tuple>
#include <tr1/type_traits>
#include <tr1/type_traits>
#include <tr1/unordered_set>
#include <tr1/unordered_set>
#include <tr1/unordered_map>
#include <tr1/unordered_map>
#include <tr1/utility>
#include <tr1/utility>
],,
],,
ac_cv_cxx_stdcxx_tr1=yes, ac_cv_cxx_stdcxx_tr1=no)
ac_cv_cxx_stdcxx_tr1=yes, ac_cv_cxx_stdcxx_tr1=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_stdcxx_tr1" = yes; then
if test "$ac_cv_cxx_stdcxx_tr1" = yes; then
AC_DEFINE(STDCXX_TR1_HEADERS,,[Define if ISO C++ TR1 header files are present. ])
AC_DEFINE(STDCXX_TR1_HEADERS,,[Define if ISO C++ TR1 header files are present. ])
fi
fi
])
])
An alternative is to check just for specific TR1 includes, such as <unordered_map> and <unordered_set>.
An alternative is to check just for specific TR1 includes, such as <unordered_map> and <unordered_set>.
# AC_HEADER_TR1_UNORDERED_MAP
# AC_HEADER_TR1_UNORDERED_MAP
AC_DEFUN([AC_HEADER_TR1_UNORDERED_MAP], [
AC_DEFUN([AC_HEADER_TR1_UNORDERED_MAP], [
AC_CACHE_CHECK(for tr1/unordered_map,
AC_CACHE_CHECK(for tr1/unordered_map,
ac_cv_cxx_tr1_unordered_map,
ac_cv_cxx_tr1_unordered_map,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([#include <tr1/unordered_map>], [using std::tr1::unordered_map;],
AC_TRY_COMPILE([#include <tr1/unordered_map>], [using std::tr1::unordered_map;],
ac_cv_cxx_tr1_unordered_map=yes, ac_cv_cxx_tr1_unordered_map=no)
ac_cv_cxx_tr1_unordered_map=yes, ac_cv_cxx_tr1_unordered_map=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_tr1_unordered_map" = yes; then
if test "$ac_cv_cxx_tr1_unordered_map" = yes; then
AC_DEFINE(HAVE_TR1_UNORDERED_MAP,,[Define if tr1/unordered_map is present. ])
AC_DEFINE(HAVE_TR1_UNORDERED_MAP,,[Define if tr1/unordered_map is present. ])
fi
fi
])
])
# AC_HEADER_TR1_UNORDERED_SET
# AC_HEADER_TR1_UNORDERED_SET
AC_DEFUN([AC_HEADER_TR1_UNORDERED_SET], [
AC_DEFUN([AC_HEADER_TR1_UNORDERED_SET], [
AC_CACHE_CHECK(for tr1/unordered_set,
AC_CACHE_CHECK(for tr1/unordered_set,
ac_cv_cxx_tr1_unordered_set,
ac_cv_cxx_tr1_unordered_set,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([#include <tr1/unordered_set>], [using std::tr1::unordered_set;],
AC_TRY_COMPILE([#include <tr1/unordered_set>], [using std::tr1::unordered_set;],
ac_cv_cxx_tr1_unordered_set=yes, ac_cv_cxx_tr1_unordered_set=no)
ac_cv_cxx_tr1_unordered_set=yes, ac_cv_cxx_tr1_unordered_set=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_tr1_unordered_set" = yes; then
if test "$ac_cv_cxx_tr1_unordered_set" = yes; then
AC_DEFINE(HAVE_TR1_UNORDERED_SET,,[Define if tr1/unordered_set is present. ])
AC_DEFINE(HAVE_TR1_UNORDERED_SET,,[Define if tr1/unordered_set is present. ])
fi
fi
])
])
Support for C++0x dialect.
Support for C++0x dialect.
Check for baseline language coverage in the compiler for the C++0xstandard.
Check for baseline language coverage in the compiler for the C++0xstandard.
# AC_COMPILE_STDCXX_OX
# AC_COMPILE_STDCXX_OX
AC_DEFUN([AC_COMPILE_STDCXX_0X], [
AC_DEFUN([AC_COMPILE_STDCXX_0X], [
AC_CACHE_CHECK(if g++ supports C++0x features without additional flags,
AC_CACHE_CHECK(if g++ supports C++0x features without additional flags,
ac_cv_cxx_compile_cxx0x_native,
ac_cv_cxx_compile_cxx0x_native,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([
AC_TRY_COMPILE([
template <typename T>
template <typename T>
struct check
struct check
{
{
static_assert(sizeof(int) <= sizeof(T), "not big enough");
static_assert(sizeof(int) <= sizeof(T), "not big enough");
};
};
typedef check<check<bool>> right_angle_brackets;
typedef check<check<bool>> right_angle_brackets;
int a;
int a;
decltype(a) b;
decltype(a) b;
typedef check<int> check_type;
typedef check<int> check_type;
check_type c;
check_type c;
check_type&& cr = c;],,
check_type&& cr = c;],,
ac_cv_cxx_compile_cxx0x_native=yes, ac_cv_cxx_compile_cxx0x_native=no)
ac_cv_cxx_compile_cxx0x_native=yes, ac_cv_cxx_compile_cxx0x_native=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
AC_CACHE_CHECK(if g++ supports C++0x features with -std=c++0x,
AC_CACHE_CHECK(if g++ supports C++0x features with -std=c++0x,
ac_cv_cxx_compile_cxx0x_cxx,
ac_cv_cxx_compile_cxx0x_cxx,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -std=c++0x"
CXXFLAGS="$CXXFLAGS -std=c++0x"
AC_TRY_COMPILE([
AC_TRY_COMPILE([
template <typename T>
template <typename T>
struct check
struct check
{
{
static_assert(sizeof(int) <= sizeof(T), "not big enough");
static_assert(sizeof(int) <= sizeof(T), "not big enough");
};
};
typedef check<check<bool>> right_angle_brackets;
typedef check<check<bool>> right_angle_brackets;
int a;
int a;
decltype(a) b;
decltype(a) b;
typedef check<int> check_type;
typedef check<int> check_type;
check_type c;
check_type c;
check_type&& cr = c;],,
check_type&& cr = c;],,
ac_cv_cxx_compile_cxx0x_cxx=yes, ac_cv_cxx_compile_cxx0x_cxx=no)
ac_cv_cxx_compile_cxx0x_cxx=yes, ac_cv_cxx_compile_cxx0x_cxx=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
AC_CACHE_CHECK(if g++ supports C++0x features with -std=gnu++0x,
AC_CACHE_CHECK(if g++ supports C++0x features with -std=gnu++0x,
ac_cv_cxx_compile_cxx0x_gxx,
ac_cv_cxx_compile_cxx0x_gxx,
[AC_LANG_SAVE
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
AC_TRY_COMPILE([
AC_TRY_COMPILE([
template <typename T>
template <typename T>
struct check
struct check
{
{
static_assert(sizeof(int) <= sizeof(T), "not big enough");
static_assert(sizeof(int) <= sizeof(T), "not big enough");
};
};
typedef check<check<bool>> right_angle_brackets;
typedef check<check<bool>> right_angle_brackets;
int a;
int a;
decltype(a) b;
decltype(a) b;
typedef check<int> check_type;
typedef check<int> check_type;
check_type c;
check_type c;
check_type&& cr = c;],,
check_type&& cr = c;],,
ac_cv_cxx_compile_cxx0x_gxx=yes, ac_cv_cxx_compile_cxx0x_gxx=no)
ac_cv_cxx_compile_cxx0x_gxx=yes, ac_cv_cxx_compile_cxx0x_gxx=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_compile_cxx0x_native" = yes ||
if test "$ac_cv_cxx_compile_cxx0x_native" = yes ||
test "$ac_cv_cxx_compile_cxx0x_cxx" = yes ||
test "$ac_cv_cxx_compile_cxx0x_cxx" = yes ||
test "$ac_cv_cxx_compile_cxx0x_gxx" = yes; then
test "$ac_cv_cxx_compile_cxx0x_gxx" = yes; then
AC_DEFINE(HAVE_STDCXX_0X,,[Define if g++ supports C++0x features. ])
AC_DEFINE(HAVE_STDCXX_0X,,[Define if g++ supports C++0x features. ])
fi
fi
])
])
Check for library coverage of the C++0xstandard.
Check for library coverage of the C++0xstandard.
# AC_HEADER_STDCXX_0X
# AC_HEADER_STDCXX_0X
AC_DEFUN([AC_HEADER_STDCXX_0X], [
AC_DEFUN([AC_HEADER_STDCXX_0X], [
AC_CACHE_CHECK(for ISO C++ 0x include files,
AC_CACHE_CHECK(for ISO C++ 0x include files,
ac_cv_cxx_stdcxx_0x,
ac_cv_cxx_stdcxx_0x,
[AC_REQUIRE([AC_COMPILE_STDCXX_0X])
[AC_REQUIRE([AC_COMPILE_STDCXX_0X])
AC_LANG_SAVE
AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
AC_TRY_COMPILE([
AC_TRY_COMPILE([
#include <cassert>
#include <cassert>
#include <ccomplex>
#include <ccomplex>
#include <cctype>
#include <cctype>
#include <cerrno>
#include <cerrno>
#include <cfenv>
#include <cfenv>
#include <cfloat>
#include <cfloat>
#include <cinttypes>
#include <cinttypes>
#include <ciso646>
#include <ciso646>
#include <climits>
#include <climits>
#include <clocale>
#include <clocale>
#include <cmath>
#include <cmath>
#include <csetjmp>
#include <csetjmp>
#include <csignal>
#include <csignal>
#include <cstdarg>
#include <cstdarg>
#include <cstdbool>
#include <cstdbool>
#include <cstddef>
#include <cstddef>
#include <cstdint>
#include <cstdint>
#include <cstdio>
#include <cstdio>
#include <cstdlib>
#include <cstdlib>
#include <cstring>
#include <cstring>
#include <ctgmath>
#include <ctgmath>
#include <ctime>
#include <ctime>
#include <cwchar>
#include <cwchar>
#include <cwctype>
#include <cwctype>
#include <algorithm>
#include <algorithm>
#include <array>
#include <array>
#include <bitset>
#include <bitset>
#include <complex>
#include <complex>
#include <deque>
#include <deque>
#include <exception>
#include <exception>
#include <fstream>
#include <fstream>
#include <functional>
#include <functional>
#include <iomanip>
#include <iomanip>
#include <ios>
#include <ios>
#include <iosfwd>
#include <iosfwd>
#include <iostream>
#include <iostream>
#include <istream>
#include <istream>
#include <iterator>
#include <iterator>
#include <limits>
#include <limits>
#include <list>
#include <list>
#include <locale>
#include <locale>
#include <map>
#include <map>
#include <memory>
#include <memory>
#include <new>
#include <new>
#include <numeric>
#include <numeric>
#include <ostream>
#include <ostream>
#include <queue>
#include <queue>
#include <random>
#include <random>
#include <regex>
#include <regex>
#include <set>
#include <set>
#include <sstream>
#include <sstream>
#include <stack>
#include <stack>
#include <stdexcept>
#include <stdexcept>
#include <streambuf>
#include <streambuf>
#include <string>
#include <string>
#include <tuple>
#include <tuple>
#include <typeinfo>
#include <typeinfo>
#include <type_traits>
#include <type_traits>
#include <unordered_map>
#include <unordered_map>
#include <unordered_set>
#include <unordered_set>
#include <utility>
#include <utility>
#include <valarray>
#include <valarray>
#include <vector>
#include <vector>
],,
],,
ac_cv_cxx_stdcxx_0x=yes, ac_cv_cxx_stdcxx_0x=no)
ac_cv_cxx_stdcxx_0x=yes, ac_cv_cxx_stdcxx_0x=no)
AC_LANG_RESTORE
AC_LANG_RESTORE
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
])
])
if test "$ac_cv_cxx_stdcxx_0x" = yes; then
if test "$ac_cv_cxx_stdcxx_0x" = yes; then
AC_DEFINE(STDCXX_0X_HEADERS,,[Define if ISO C++ 0x header files are present. ])
AC_DEFINE(STDCXX_0X_HEADERS,,[Define if ISO C++ 0x header files are present. ])
fi
fi
])
])
As is the case for TR1 support, these autoconf macros can be made for a finer-grained, per-header-file check. For <unordered_map>
As is the case for TR1 support, these autoconf macros can be made for a finer-grained, per-header-file check. For <unordered_map>
# AC_HEADER_UNORDERED_MAP
# AC_HEADER_UNORDERED_MAP
AC_DEFUN([AC_HEADER_UNORDERED_MAP], [
AC_DEFUN([AC_HEADER_UNORDERED_MAP], [
AC_CACHE_CHECK(for unordered_map,
AC_CACHE_CHECK(for unordered_map,
ac_cv_cxx_unordered_map,
ac_cv_cxx_unordered_map,
[AC_REQUIRE([AC_COMPILE_STDCXX_0X])
[AC_REQUIRE([AC_COMPILE_STDCXX_0X])
AC_LANG_SAVE
AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
AC_TRY_COMPILE([#include <unordered_map>], [using std::unordered_map;],
AC_TRY_COMPILE([#include <unordered_map>], [using std::unordered_map;],
ac_cv_cxx_unordered_map=yes, ac_cv_cxx_unordered_map=no)
ac_cv_cxx_unordered_map=yes, ac_cv_cxx_unordered_map=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_unordered_map" = yes; then
if test "$ac_cv_cxx_unordered_map" = yes; then
AC_DEFINE(HAVE_UNORDERED_MAP,,[Define if unordered_map is present. ])
AC_DEFINE(HAVE_UNORDERED_MAP,,[Define if unordered_map is present. ])
fi
fi
])
])
# AC_HEADER_UNORDERED_SET
# AC_HEADER_UNORDERED_SET
AC_DEFUN([AC_HEADER_UNORDERED_SET], [
AC_DEFUN([AC_HEADER_UNORDERED_SET], [
AC_CACHE_CHECK(for unordered_set,
AC_CACHE_CHECK(for unordered_set,
ac_cv_cxx_unordered_set,
ac_cv_cxx_unordered_set,
[AC_REQUIRE([AC_COMPILE_STDCXX_0X])
[AC_REQUIRE([AC_COMPILE_STDCXX_0X])
AC_LANG_SAVE
AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_LANG_CPLUSPLUS
ac_save_CXXFLAGS="$CXXFLAGS"
ac_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
CXXFLAGS="$CXXFLAGS -std=gnu++0x"
AC_TRY_COMPILE([#include <unordered_set>], [using std::unordered_set;],
AC_TRY_COMPILE([#include <unordered_set>], [using std::unordered_set;],
ac_cv_cxx_unordered_set=yes, ac_cv_cxx_unordered_set=no)
ac_cv_cxx_unordered_set=yes, ac_cv_cxx_unordered_set=no)
CXXFLAGS="$ac_save_CXXFLAGS"
CXXFLAGS="$ac_save_CXXFLAGS"
AC_LANG_RESTORE
AC_LANG_RESTORE
])
])
if test "$ac_cv_cxx_unordered_set" = yes; then
if test "$ac_cv_cxx_unordered_set" = yes; then
AC_DEFINE(HAVE_UNORDERED_SET,,[Define if unordered_set is present. ])
AC_DEFINE(HAVE_UNORDERED_SET,,[Define if unordered_set is present. ])
fi
fi
])
])
Container::iterator_type is not necessarily Container::value_type*
Container::iterator_type is not necessarily Container::value_type*
This is a change in behavior from the previous version. Now, most
This is a change in behavior from the previous version. Now, most
iterator_type typedefs in container classes are POD
iterator_type typedefs in container classes are POD
objects, not value_type pointers.
objects, not value_type pointers.
Bibliography
Bibliography
Migrating to GCC 4.1
Migrating to GCC 4.1
Dan
Dan
Kegel
Kegel
Building the Whole Debian Archive with GCC 4.1: A Summary
Building the Whole Debian Archive with GCC 4.1: A Summary
Martin
Martin
Michlmayr
Michlmayr
Migration guide for GCC-3.2
Migration guide for GCC-3.2